Ray A. Sallan, DDS

Science and Technology Associate













As a clinician, dental surgeon, and a practitioner with 20 years of experience, spanning 5 major cities and thousands of patients, I tackled mostly the diagnostic, surgical and application aspects of my profession. Throughout my career and as I practiced, many questions that were initially rooted in my biology background arose and I became increasingly eager to find answers to them.

One of which is jaw and tooth morphological coevolution. While modern occlusion has been extensively studied from a dental perspective, the evolutionary relationship between jaw and tooth is difficult to discern from current paleontological studies. Mastication with precise occlusion (teeth of opposing arches connecting on specific and exact locations) has led to increased caloric intake efficiency, allowing animals (mammals in particular) to diversify their selection of food resources improving survivability and increasing habitat geographical range. The efficiency of converting food sources to energy is perhaps (second to the innate ability of species to evolve) the most important and critical characteristic of all life on our planet. From early tetrapods like Diadectids to modern humans, mastication and occlusion has changed considerably where jaw mechanics and tooth morphology convergently evolved to serve the critical purpose of efficient mastication. My aim is to use a combined dental and paleontological approach to find the key to this parallel evolution and to determine if there are unique factors guiding it.